Car-brake



2 Sheets-Sheen 1.

T. S. E. DIXON.

(No Model.)

OAR BRAKE.

Patented Oct. 29, 1.889.

2 Sheets-Sheen 2.

(No Model.)

T. s. E. DIXON.

GAR. BRAKE.

Patented Oct. Z9, 1889.

72a Ve 2240 UNITED STATES PATENT OFFICE.

THERON S. E. DIXON, OF CHICAGO, ILLINOIS.

CAR-BRAKE.

SPECIFICATION forming part of Letters Patent No. 414,108, dated October 29, 1889.

Application filed August l0, 1889. Serial No. 320,382. (No model.)

T0 @ZZ whom t may concern.-

Be it known that I, THERON S. E. DIXON, a citizen of the United States of America, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Car-Brakes, of which the following is a specification.

Referring to the accompanying drawings, wherein similar referenceletters indicate the same or corresponding parts, Figure l is a top plan of the' truck, showing a practicable arrangement of the brake levers and rods. Fig. 2 is a vertical cross-section in line 2 2 of Fig. l, including also the car-transom- Fig. 3 is a horizontal section through the truckbolster, showing a modiiication. Fig. 4 is a vertical section of said modification, taken in lines 4 4 of Fig. 3. Fig. 5 is a vertical section showing another modification. Fig. 6 is a vertical section at right angles to the section shown in Fig. 5, and Fig. 7 represents a modification of the structure shown in Fig. 5.

The object of this invention is to provide a simple, cheap, effective, and therefore practical, means for automatically limiting the maximum brake-pressure of each car-truck by the weight carried by such car-truck without interfering with the normal operation of the brake mechanism when the pressure is below the maximum allowed for such weight, to the end that the wheels may be prevented from sliding on the track and yet receive all the brakepressure which they are able to receive without danger of sliding.

The invention consists in the mechanical devices and combinations described in the following specification, and more particularly indicated in the claims appended thereto. It is especially adapted to the brake-gear of the Stevens, Hodge, and similar systems having a brake-lever for each brakedoeam and transmitting the power from the brake rod or chain first to one of said levers and thence by a connecting rod, chain, or bar to the other, so as to get an equal brake-pressure on both pairs of wheels.

For clearness of description I will term the brake-lever which receives power directly from the brake-rod the Iirst lever, and that which receives power from the connecting rod ,bar, or chain the second lever,of the sys tem, and will prelilninarily call attention to the fact th at heretofore in this class of brakes the second lever has always had one end articulated to some fixed part of the truck.

The most important of the novel principles involved in my invention consists, iirst,in removing` the rigid connection of the second lever and substituting a moving connection to a lifting device, which lifts against the weight of the car, so that bot-h levers, instead of being held to their work by the rigid connection of the second, are held to their work by the weight of the car acting against the last end of the second lever; secondly, in employing as a lifting device for the purpose aforesaid a simple pry or crow-bar lever in serted between the truck-bolster and the carbolster and tending merely to pry them apart; thirdly, arranging the pry transversely to said bolster and making it in the form of a bellcrank to avoid the necessity of introducing between the second lever and the pry devices for changing the direction of motion; and, fourthly, making the pry in the form of a combined lever and cam to increase its lifting-power, and at the same time insure its automatic return to its normal position after its work has been performed. These principles may be applied conjointly or separately with various modifications in the form of the mechanical devices. As illustrated in the drawings, they are all applied in one apparatus,which I will now proceed to describe.

In the drawings, a a indicate the carwheels; l) b', the brake-beams; b2, the braken shoes; c, the first brake-lever; c', the second brake-lever; c2, the point at which each brakelever is articulated to its appropriate brakebeam; c3, the brake rod, chain, or bar by which power is transmitted from the windlass or brake-cylinder to the brake-lever c; c4, the connecting rod, bar, or chain by which power is transmitted from the first to the second brake-lever; d, the truck-bolster; f, the carbolster; g, the lower center plate or chairplate, attached to the truck-bolster; h, the up= per center plate or chair-plate, att-ached to the car-bolster and resting upon the plate g; e', the king-bolt, extending down through the center plates; and j j, the usual side bearings. These parts are of any ordinary construction IOO and may be modified in any suitable way to adapt them to the application of my invenf tion to different forms of car-truck.

Taking this old and well-known construction, it is only necessary by'my invention to apply one additional partto wit, a liftinglever e, arranged transversely to the two bolsters-and to connect the last end of the second lever c to such lifting-lever instead of to the car-truck, as heretofore, in order to leave the brakes perfectly free to operate in the usual manner so long as their force is insufficient to slide the wheels, whether the cars be empty or loaded,and to arrest their operation only when the pressure becomes suchas to -endanger sliding.

The pry e maybe applied to the `holsters at the center plates or at any point or points between said plates and the end of the bolsters. The advantage of arranging it in4 the latter position is that it requires no change in the usual inclined position of the second lever c', and that of arranging it in the for mer position is that it lifts both sides of the C31 equally. The constructer is at liberty to use either arrangement, ,as he may deem best, the effective principle being the same in' both cases, because, if the car be loaded evenly, as itv should be, the resistance to the liftiriglle- 'ver will be proportionate to the weight borne by the truck in either case. `The weight to be actually lifted by the lever will of course vary with the point of. its application to the b olsters; but the constructer will compensate for this variation by vvarying the ratio of leverage.

In Figs. 3, 4, 5, 6, and 7 the lifting-lever is shown as applied at the center plates, and in Figs; l and 2 as applied between the center plates and the end of the holsters.

Preferred details of application are as folljows: First, when applied at the center plates, I provide the lower plate g with a recess to accommodate thershort arm of the pry e, so

that the latter will `rest on or in -thelower plate and pry against the upper plate h, any suitable means-for example, trunnions or a bosslying in a recess in the center plate-being employed to retain the lever in place; I also preferably slot t-he end of the lifting-lever vertically, as shown in Fig. 3, to enable it to lift -at both sides of the king-bolt. The long arm of the lever e is connected to the last end of lever c by any suitable meansfor example, by a rod, chain, or bar e. When applied away from the center plates,I attach plates h g to the two bolsters, as shown in Fig. 2, arranging the end of the lever e in a recess in the lower plate, so that it will lift against the upper plate, as already described..

In either position the lever e may, if preferred, be pivoted below the truck-bolster by a hanger It and lift the car-bolster by means of a lifting-bolt m, extending up through the former against the bearing-plate of the latter. In this arrangement the hanger may be regard ed as constituting substantially a part of Fig. 2 with a rounded head e3, which acts as i a cam to aid in lifting the car, so that by reason of theincreased power the long arm of the lever may be considerably shortened.

In all the drawings thelifting-lever is lshown in the form of a bell-crank, which admits of a straight connection to the lever c.

Figs l to 6, inclusive, show the invention applied to outside-hung brakes'. With slight mOi-iieatiOns, hardly necessary to describe, it may equally as -Well be applied to inside-hung i brakes-for exam ple, by shifting the fiilc'r'uinpoint tothe end of the short and bending the long arm out far enough to give it sufficient clearance, as indicated in Fig. 7;

The greatadvantage of this improvement is that'it combines efficient and certain operation with estreme simplicity and cheapnjess of construction. It involves no .change in the standard brake-gear now in use, no `special form of car-truck-being adapted or capable of easy adaptation to any of the standard trucks by means of simple and cheap appliances-and no special adjustment of the normal distance between the brake-shoesand the wheels.

In applying the brakes the first movement of thebrake-rod 4ci] acts to take up the slack, whatever it may be, and set the shoes against the wheels. Thereafter the weight of the car holds the brake-levers to their work and enables them to apply their -full force to the IOO IIO

car-wheels so long vas the car does not lift;

but when`V the car lifts, all furtherforce applied by the brake-rod is'expended in raising the car, Without increasing the pressure of the shoes on the wheels. InV other words, when the shoes act `against the wheels my improvement comes into operation to fulcrum the brake-levers against the wheels, apply the power to one end of the lever c', and hold the other end in place by the weight of the car, so that the brakes will act as usual till their limit of maximum pressure is attained, and the maximum pressure will always be directly proportional to the weight of the car and its load, and will be ascertained by multiplying the weight which bears on thelever into the ratio of leverage.

The device may be applied on Vboth trucks of a car, if preferred; but with the present systems of brakegear, which connect the brakes of one truck to those of the other, so that they are operated alike on both, there will be no special advantage in applying it to more than one, because when the brake-levers of either truck yield by the rising of the car the eiect will be communicated equally to the brake-levers of the other truck.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In a car-brake, the combination of the car-truck with a lever attached between its ends to a brake-beam Vand having one end connected to a rod, chain, or bar bywhich exterior power is transmitted to set the brakes and the other end connected to a device held in normal position by the weight or a portion of the weight of the car and adapted to yield when the force applied to it attains a predetermined relation to said weight, whereby the exterior power transmitted to set the brakes is limited in its effect to a maximum determined by the weight of .the car, substantially as described.

2. In a car-brake, the combination of the truck and brake-beams with a first and second lever by which exterior power is applied to set the brakes, the end of the second lever being secured by a yielding attachment which yields when the force applied thereto attains a predetermined relation to the weight, whereby the exterior power transmitted to set the brakes is limited in its effect to a maximum determined by'the weight of the car resting on the truck, substantially as described.

3. In a car-brake, the combination of the car, the truck, and the brake-beams with a series of connected brake-levers which trans-V mit exterior power applied to set the brakes from one to another, and thus divide and equalize it, as described, and means whereby the last lever of the series is held to its work by the weight of the car resting on the truck, but permitted to yield when the force applied to it attains a predetermined relation to such weight, whereby the exterior power transmitted to set the brakes is limited in its effect to a maximum determined by the weight of the car, substantially as described.

et. In a car-brake, the combination of the car, the truck, the brake-beams, and the brake-levers with a bell-crank lever having its short arm arranged to pry the car and truck apart and its long arm actuated bythe brake mechanism through which exterior power is transmitted to set the brakes, and whereby the car-wheels are relieved from excessive pressure by the yielding of the car, substantially as described.

5. In a car-brake, the combination of the car, the truck, the brake-beams, and the brake-levers with a cam-lever arranged be` tween the car and truck-bolster and when operated in the act of setting the brakes tending to force them apart by its cam-power and its leverpower, and thereby to relieve the carwheels from excessive brake-pressure, sub stantially as described.

G. In a car-brake, the combination of the following elements, viz: a metal plate or casting attached to the underside of the carbolster, a metal plate or casting attached to the upper side of the truck-bolster directly beneath the plate or casting iirst mentioned and having a recess formed therein to accommodate the end of the lifting-lever, and a liftingdever having its short arm retained in said recess and lying between said plates, so as to pry them apart and lift the car to relieve the car-wheels from excessive brakev pressure, substantially as described.

7. In a car-brake, the combination of the truck and brake-levers which transmit exterior power to set the brakes, with an addi` tional lever which affords by its connection a fulcrum in the system of brake-levers and is itself so fulcrumed as to tend to lift the car, whereby the system of brakedevers transmits and applies the braking-power and the addin tional lever limits the maximum of power applied in proportion to the weight of the car, substantially as described.

'lI-IERON S. E. DIXON. Witnesses:

L. HILL, H. BITNER. 

